Sending a variable Byref to a class

[Graff]

I want to be able to send a Richtextbox to one of my classes byref so that updates to the class rtb will update the actual rtb

Right now I have

Public Class InfLog
 
    Private Buffer1, Buffer2 As String
    Private Interval As Integer = 500
    Private rtxtbox As RichTextBox
 
    Public Sub New(ByVal Buffer1 As String, ByVal Buffer2 As String, ByRef rtb As RichTextBox)
        Me.Buffer1 = Buffer1
        Me.Buffer2 = Buffer2
        Me.rtxtbox = rtb
    End Sub

However when I make changes to rtxtBox nothing happens. Can someone please point me in the right direction?

[alextyx]

Dear Graff, I'm quite a newbie, so it's possible I fail completely, but I think you have to act on rtb directly.

Your ' Me.rtxtbox ' is private and I think it's not possible to refer it out of your class, so probably you need to complete your loop in this way, for example

rtb.text=Me.rtxtbox.text

At this time, I think, you will see the changes.

Problem is: you have to pass your variable from the constructor procedure, to that one will make the changes.

I have no good practice, anyway. Normally I pass control byref, but directly to the class public method I call and not in the constructor, where, in general, I only pass initializing parameter.

Below is an example of a class I use to redim form on my two screens.

Sub New()
 
        End Sub
 
        Public Function FnzRapportoTraSchermoEForm(ByRef F As Form) As Single
 
            Dim orizz As Integer
            Dim vert As Integer
 
            Me.SubRilevaRisoluzione(F, orizz, vert)
            Dim R As Single = CSng(orizz / F.Width)
 
            Return R
 
        End Function
 
        Private Sub SubRilevaRisoluzione(ByRef IlForm As Form, ByRef Orizzontale As Integer, ByRef Verticale As Integer)
 
            Dim desktopSize As Size
            desktopSize = System.Windows.Forms.SystemInformation.PrimaryMonitorSize
            'Dim AreaSchermo As System.Drawing.Rectangle = Screen.GetWorkingArea(IlForm)
            Dim Punto As System.Drawing.Point
            Punto.X = IlForm.Left + (IlForm.Width / 2)
            Punto.Y = IlForm.Top + (IlForm.Height / 2)
            Dim AreaSchermo As System.Drawing.Rectangle = Screen.GetWorkingArea(Punto)
            Verticale = AreaSchermo.Height
            Orizzontale = AreaSchermo.Width
            'MessageBox.Show(Pluto.ToString & "   " & paperino.ToString)
 
        End Sub
 
 
        Public Sub SubVariaSecondoRapporto(ByRef F As Form, ByVal Rapporto As Single)
 
            Dim R As Single = CSng(Rapporto)
            f.Scale(R)
            Me.CambiaIFont(f, R)
            'F.Refresh()
 
        End Sub
 
 
 
        Private Sub CambiaIFont(ByRef F As Form, ByVal R As Single)
 
            Dim Ct As Control
            Dim T As String
 
            For Each Ct In F.Controls
                If Not Ct.Controls Is Nothing Then
                    'Se qui, contiene controlli di secondo livello (figli)
                    Dim CtF As Control     'Devo ciclare sui suoi controlli figli
                    For Each CtF In Ct.Controls
                        Me.RidimensionaFontDelControllo(CtF, R)
                    Next
                End If
 
                ' Qui si maneggiano i controlli di primo livello
                Me.RidimensionaFontDelControllo(Ct, R)
 
            Next
 
        End Sub
 
 
        Private Sub RidimensionaFontDelControllo(ByRef Ct As Control, ByVal R As Single)
 
            Dim FSize As Single = Ct.Font.Size
            Dim FStile As FontStyle = Ct.Font.Style
            Dim FNome As String = Ct.Font.Name
            Dim NuovoSize As Single = FSize * R
            Dim NFont As New Font(FNome, NuovoSize, FStile)
            Ct.Font = NFont
 
        End Sub
 
 
    End Class

Good job!

[Pirate]

Even ByVal should result the same (in case you've done it right).

[alextyx]

Pirate is right, because we are speaking about a RichTextBox that is an object 'reference type' and not 'value type'.

We have to remember, that If we use a variable like a Double, or a String, we have to specify which kind of 'link' we need because it makes a difference.

Good morning to both, dear friends

[Pirate]

RichTextBox is a Class , dude.

[alextyx]

What is the point?
You are underlying that Rtb is a class....perhaps because I said it is an object? If so, that's because when you work with something, it is an object (a class instanced....or instanciated...damned my english....help me! ). A form is a class, but when you try to refer it without an instance (an object) you have an error. You are perfectly right saying richtextbox is a class, but 'YourRtb', placed on your form, is an object derived from its class. It's possible I'm wrong, obviously, so I don't want to say 'that's true!'. But only 'I THINK IT'S TRUE'. If not, I will note my mistake and will become a little more experienced learning by that!
Anyway we are discussing about details that are not really the 'core' of the thread, also if interesting'.

[alextyx]

Or...perhaps you wanted to say that class is reference type? In this case I agree 100%: Classes are reference types!
Excuse me...I'm not very sure of my english and sometimes I miss also what should be obvious!

[jwebster03]

you've gone mad.

[<ABX]

Public Class InfLog
 
    Private Buffer1, Buffer2 As String
    Private Interval As Integer = 500
    Private rtxtbox As RichTextBox
 
    Public Sub New(ByVal Buffer1 As String, ByVal Buffer2 As String, ByRef rtb As RichTextBox)
        Me.Buffer1 = Buffer1
        Me.Buffer2 = Buffer2
        'you problem lies here:
        'rtb is a reference to the rtb....
        'when you say 'Me.rtxtbox = rtb' vb thinks you want to
        'create a copy of the object rtb is pointing to and store it in
        'Me.rtxtbox
        Me.rtxtbox = rtb
    End Sub

at this very moment, i cant think of away to copy a reference (pointer). Prolly because of lack of sleep....

[Pirate]

Originally posted by alextyx
What is the point?
You are underlying that Rtb is a class....perhaps because I said it is an object?

I didn't mean to make any confusion but 'Object' is general word for class instances(RTB instance ...) and base datatypes(Int,String,Double..etc) which could be confusing also when talking about value types and reference types .Umm , there's much has to be said though , but I'm just a little lazy ...

[alextyx]

Yes Pirate. Be patience, as I said sometimes I'm lost trying to figure if what I wrote means really what I wanted to and, if not, what could have you understood.....very stressing!

Just now I'm having a look of a list of reference and value types, to refresh my memory about. I confirm...Classes are reference type!

Jewbster....I agree with you !

[Graff]

Ok so the only solution we really know of is to take it out of the initialization and put it in my methods that will use it when called in the main program?

[techgnome]

I think we've only been looking at the apples and calling the whole fuit salad bad...

How is this class being dimmed, instanciated, and used?

Personaly, I cannot see anything wrong with the constructor. I'm wondering if maybe it's wrong at the other end of things.

TG

[Graff]

In the global area of the form main:
Dim iLog as Inflog

In Form_Load event:
iLog = New InfLog("B1.UBL","B2.UBL", rtbChat)

Then in the btnEnable_Click event:

tMain.enable = true 'this is a timer

tMain_Tick event:

iLog.refresh()

at which point the refresh method will parse a log, color code it determined by certain delimiters in the log and put it on the rtbChat control

I was hoping to avoid passing the rtbChat down 3 methods withing the InfLog class by just refrencing it in as a part of the class so instead of declaring it at the constructor I have to go

iLog.refresh(rtbChat)

refresh called the process method

Process(rtbChat)

then process calls the parseline method

ParseLine(rtbChat)

where finally alll the magic is done.